On Mon, 12 Apr 2010 13:27:45 +0100 Russell King <rmk@xxxxxxxxxxxxxxxx> wrote: > On Sun, Apr 11, 2010 at 11:06:09PM -0700, David VomLehn wrote: > > This patch makes panic() and die() registers available to, for example, > > panic notifier functions. Panic notifier functions are quite useful > > for recording crash information, but they don't get passed the register > > values. This makes it hard to print register contents, do stack > > backtraces, etc. The changes in this patch save the register state when > > panic() is called and introduce a function for die() to call that allows > > it to pass in the registers it was passed. > > Can you explain why you want this? > > I'm wondering about the value of saving the registers; normally when a panic > occurs, it's because of a well defined reason, and not because something > went wrong in some CPU register; to put it another way, a panic() is a > more controlled exception than a BUG() or a bad pointer dereference. I'm curious about the potential use case as well. So far I only wanted to know the registers if the panic has been triggered due to an unexpected fault with panic_on_oops=1 or in_interrupt()==1. If that happens the die() handler prints the registers. An open coded panic is easy to analyze, imho no need for the registers. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
